| 摘要 |
<p>Electromagnetic driving unit for a loudspeaker assembly provided with a frame (202) and a diaphragm (31). The driving unit comprises a magnet part and a coil part (21) for magnetic cooperation with the magnet part, the coil part being translatable along a translation axis with respect to the magnet part. The diaphragm (31) may extend from the coil part in a substantially radial direction with respect to the translation axis (23) of the coil part. The magnet part comprises two permanent magnets (11, 12) and an intermediate magnetic pole element (13) which is sandwiched between the permanent magnets when viewed along the translation axis of the coil part. In order to improve the efficiency of the driving unit, the magnet part further comprises two external magnetic pole elements (14, 13). The permanent magnets and the intermediate magnetic pole element are sandwiched between the external magnetic pole elements, all pole elements having pole faces which are magnetically directed towards the coil part.</p> |
